The Gastropod is a Hard Mode flying enemy that shoots pink-colored lasers, named "pink laser" by the game, that are fast and travel in straight lines. They are very common, and sometimes appear in groups. Shooting the Gastropod while it is preparing its laser will cause it to retreat back into its shell and not shoot the charging shot. It also has the ability to snipe the player from off-screen, making its attacks hard to dodge. Their attack is similar to that of the Probes spawned by the Destroyer.

Trivia

A Gastropod is the term used to describe snails and slugs, meaning "stomach-foot". It also refers to any mollusk of the class Gastropoda, including snails, whelks, slugs, etc.